gemini-cli - 💡(How to fix) Fix [BUG] PTY Master Device Exhaustion (ENXIO) on macOS after prolonged usage in YOLO mode [3 comments, 3 participants]

After running gemini-cli (v0.38.1) for an extended period (weeks) with --approval-mode yolo, the system eventually hits the macOS PTY limit (kern.tty.ptmx_max = 511), preventing any new terminal sessions from opening system-wide with the error: Device not configured.

TL;DR

The issue can be mitigated by terminating the long-running gemini-cli process and restarting it periodically to release the accumulated PTY descriptors.

Guidance

• Investigate the --approval-mode yolo configuration to understand its impact on PTY descriptor management, as it may be contributing to the leak.
• Monitor the PTY count using lsof | grep "/dev/ptmx" | wc -l to detect when the system is approaching the limit.
• Consider implementing a periodic restart of the gemini-cli process to prevent the descriptor leak from accumulating over time.
• Review the related issues #22814 and #22001 to see if there are any known fixes or workarounds for the file descriptor leak in ShellExecutionService and Terminal Instance Resource Retention.

Example

No code snippet is provided as the issue is related to a specific configuration and system resource management.

Notes

The provided guidance is based on the assumption that the gemini-cli process is not properly releasing PTY descriptors, leading to the system-wide limit being reached. The actual root cause may be more complex and require further investigation.

Recommendation

Apply workaround: Implement a periodic restart of the gemini-cli process to prevent the descriptor leak from accumulating over time. This is recommended because it provides a temporary solution to mitigate the issue until a more permanent fix is available.